cool photos, what caused the abnormal wear ? do both engines have approx the same history ?

Apologies gremlin-I am not sure of the reason of this wear. AFAIK it is due to poor running in.

Classic 500's sold in India do not have O2 sensor. Initial bikes suffered from missing/jerking/cold starts issue. RE issued a temporary solution in the form of higher heat range plugs and later Bosch Platinum Plus WR8DP plugs. Ultimately they have remapped all bikes with new maps which has fixed these issues and Platinum Plus is now provided in all C5's from the factory.

Has anyone got a UCE head gasket laying around, and might be able to measure the thickness with a dial-caliper, so I can know the distance of the head from the barrel?I just have the head only here right now.

Has anyone got a UCE head gasket laying around, and might be able to measure the thickness with a dial-caliper, so I can know the distance of the head from the barrel?I just have the head only here right now.

Hi ace.cafe

I would love to help and can go to RE ASC tomorrow or the day after and can ask them to show me a new UCE head gasket, but I do not have a dial-caliper. Is there any other commonly available instrument which can be used to measure the thickness? Can a ruler be used?

Hi,I suppose you could use anything that could read pretty accurately at that size.It's probably thin enough that you'd have to use a ruler with very fine graduations.I suspect it could be in the area of about 0.5mm-1.0mm.

Any vernier caliper could do it, or a micrometer, or a very finely graduated engineer's ruler. The more accurate the measurement, the better. But anything close is better than nothing.

If you have the time and inclination to try it, I'd appreciate the help for the cause!

I think it runs too rich on the highway ( 7/8 ~ 8/8 throttle ). I'm *really* looking forward to the work ACE is doing here. If we can get the throttle down to something like 70% when cruising at 75 MPH I believe the system will re-enter closed-loop mode and start reading the O2 sensor to trim the mixture.

Apologies gremlin-I am not sure of the reason of this wear. AFAIK it is due to poor running in.

Classic 500's sold in India do not have O2 sensor. Initial bikes suffered from missing/jerking/cold starts issue. RE issued a temporary solution in the form of higher heat range plugs and later Bosch Platinum Plus WR8DP plugs. Ultimately they have remapped all bikes with new maps which have fixed these issues and Platinum Plus is now provided in all C5's from the factory.

Our main guy who does most of our work at Mondello's has been on vacation for the last 2 weeks, so not much happening until he gets back.

Basically, there will be a number of experiments to see how the head responds to various things, and then some decisions will be made about proceeding."Bang for the buck" will play a large part. There's always a sweet spot on the "diminishing returns" curve that we like to aim at.

One thing that looks potentially promising is that we may be able to use the Fireball valve spring system in this head, with some seemingly "minor" adjustments.

I would not move the O2 sensor. It is placed where it is placed for scientific reasons and is very important. No amount of "mind grinding" is going to change that. I have had this discussion with the engineers from RE and Keihin. It is also placed so that it sheds the maximum amount of moisture which can contribute to failure.

Where did we get the idea that the bike is not in closed loop operation at higher speeds?

I suppose it wouldn't lead to a legally saleable product but I would be fascinated to find out what a developed UCE motor would produce with a good quality flat slide carburetor bolted on and all the EFI gubbins stripped off.